• Class: Heavy Lanthinides
• Period: 6
• IUPAC group: 3
• Traditional: IIIa

• Discovered in: 1880 by de Marignac
• Origin of name: Gadolin, a Finnish chemist
• Historical or alternate name:

Gadolinite,monazite & bastnasite are the chief commercial sources

Silvery white metal. Reacts slowly with water and Oxygen. Dissolves in acids.

• Atmosphere: ~0.0 ppm
• Primitive mantle: 0.459 ppm
• Sea water: 2e-7 ppm
• Metallic meteorite: 0.196 ppm
• ConTinental crust: 3.3 ppm
• Solar photosphere: 1.12 log of abundance
• Oceanic crust: 4.6 ppm
• Solar system: 0.331 relative to Si=1.0e6

   Hazards

Metal ignites and burns readily. Compounds moderately toxic by ingestion..

• Lower:
• Upper:

Gadolinium Physical Properties

 Transitional Data

• State: Solid
• Density: 7.9004 g/cm3

 Molar enthalpy

• Atomization: 398.94 kJ mol-1
• Fusion: 15.5 kJ mol-1
• Vaporization: 301 kJ mol-1

 Transition points

• MelTing point: 1586.0 K
• Boiling point: 3539.0 K
• Critical temperature: 8670.0 K

 Molar properties

• Atomic weight: 157.25 g/mole
• Molar volume: 20.027 cm3 mol-1

 Crystal structure sequence

hexagonal-close-packed <1535 K < body-centered-cubic < melTing point

 Thermodynamics

• State: solid
  • Enthalpy 0
  • Gibbs function 0
  • Entropy 68.07
  • Heat Capacity 37.03

• State: gas
  • Enthalpy 397.5
  • Gibbs function 359.8
  • Entropy 193.314
  • Heat Capacity 27.547

 Miscellaneous physical

• Electrical resistivity: 140.5 µ-ohms/cm
• Debye temperature: 200.0 K
• Thermal conductivity: 10.6 W / m / K
• Coefficient of linear expansion: 5.0Coef. per K
• Mass magnetic susceptibility: 6.030e-5
• X-ray diffraction mass absorption coefficients:
• CuK: 439 (µ/p)/cm2 g-1
• MoK: 64.4 (µ/p)/cm2 g-1

Gadolinium Chemical Properties

 Chemical basics:

• Oxidation states: +3
• Molecular wt: 157.25 g/mole

 Radii

• Covalent: 161 pm
• Atomic: 180.4 pm
• Van der Waals: pm

 Ions:

• ion: +3 pm 93.8

 Covalent bonds

 Effective nuclear charge

• Slater: 2.85
• Clementi: 8.22
• Froese-Fischer: 11.28

 Electronegativity

• Pauling:
• Allred-Rochow: 1.11

 Standard reactions

Gadolinium Nuclear Properties

• Known 17
• Listed 16

• Known 145 - 161
• Listed 146 - 160

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 48.3 days
  • Decay mode: E.C., Beta+
  • Source: reactor
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 90.0 years
  • Decay mode: alpha,
  • Source: reactor
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 9.5 days
  • Decay mode: E.C., alpha,
  • Source: reactor
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 1.8 E6 years
  • Decay mode: alpha,
  • Source: reactor
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 120.0 days
  • Decay mode: E.C., alpha,
  • Source: reactor
• Notes

• % Occ.:Natural 0.20%
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 1.1 E14 years
  • Decay mode: alpha,
  • Source: reactor
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 242.0 days
  • Decay mode: E.C.,
  • Source: reactor
• Notes

• % Occ.:Natural 2.18%
• Mossbauer NRA: 19.70 *
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 14.80%
• Mossbauer NRA: 9.61
• Nuclear spin/Quantum no.: 3/2
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA: 13.90
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA: 16.90
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 20.47%
• Mossbauer NRA: 14.30
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 15.65%
• Mossbauer NRA: 8.73
• Nuclear spin/Quantum no.: 3/2
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA: 10.30
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 24.84%
• Mossbauer NRA: 12.70
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 21.86%
• Mossbauer NRA: 12.10
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• Isotope Cross-section 49000±2000 barns

• Absolute sensitivity: 4.11e-5 1H=1.0
• Relative sensitivity: 2.79e-4 1H=1.0
• Receptivity: 0.124 13C=1.0
• Magnetogyric ratio: -0.8273e7 rad / T / s
• Quadropole moment: 1.6e-28 m2
• Frequency: 3.819 MHz
• Reference:

Gadolinium Energy Properties

Electrons

• Ground state electron configuration: [Xe] 4f7 5d1 6s2
• Electron affinity: <=50 kJ mol-1
• Filling orbitals:

Spectral lines

 Ionization energies

 Atomic energy levels